The invention relates to a substrate comprising a plurality of rows of electrically conducting interconnection structures for realising an electrical contact, particularly a pressure contact.
The invention also relates to a device in which such a substrate is mounted on a supporting body.
A substrate of the type described in the opening paragraph is described in Japanese Kokai 60-262430. The substrate is an integrated circuit, and is bonded to a supporting body by means of the so-called flip-chip technique (face-down bonding). The interconnection structures or bumps on the substrate establish an electrically conducting pressure contact with conductor tracks on the supporting body. The pressure contacts are maintained by means of a thermosetting resin between the supporting body and the integrated circuit, which resin is cured after establishing the contacts.
A problem with such connections is their thermal behaviour. Due to different coefficients of expansion of the resin, supporting body, substrate and materials of the interconnection structure (bump), curvatures may occur, notably in the substrate and the supporting body, so that the pressure at the area of the contacts is not constant. This gives rise to unreliable contacts.